Blaster 2 and Blaster 2.5 Builds

Hey all, like I don't have enough irons in the fire here with my molded project and getting ready for contests... I have decided to build a pair of Blasters to supplement my home brewed arsenal. I have spent so much time making tooling for the other planes that with flying season here, I don't have enough airframes to make me comfortable. With that being said, I have acquired a conventional Green over Black Blaster 2 and a Flourescent Pink Blaster 2.5.

I will apologize in advance that my other two threads will probably not get alot of attention for the next couple of weeks as I finish and trim these two birds, but I think the world has a place for another moldie assembly discussion... especially since the Blasters come with no instructions at all.

First off, I want to point out my understanding of the version differences. They're pretty clearly from the same molds. The B2.5 wing (also called the "lite" in a few places) comes in around 15g lighter than the conventional wing. Mine is 142g against 158g for the B2. The servo holes are visible in the new version, but they're not indented like they were on the older model to take the servo covers. Also, the reinforcement pads in the flapperons has moved inboard on the new wing to allow for center placement of the rods coming from the aft part of the fuse. Other than these two changes and the weight difference, I cannot find any differences between the wings, even when holding them up to the light and looking "inside."

My B2 wing (green) was damaged in shipment so I had to do some light repair to it and splash it with some white paint on the tips to cover the repair and to make it more visible. It's not safe when Gavin and I have the same airplane in the same colors either... in fact it's seldom safe when Gavin and I fly together at all.

Below are some general pics of the two versions. The green fuse, green wing, and green tails are the older B2, and the Pink wing, Pink and Black tails, and Yellow fuse are the new B2.5 lite version. BTW... come on Barry. Enough with the yellow fuses already.

So the first order of business... reinforce the older style B2 fuse. I have personally witnessed four of these older fuses go kaboom on launch. They always break about an inch behind the fuse joint, probably due to the thin skins not being able to handle the compression loads when the fuse tries to bend. For that reason, I'm putting a piece of 80g/sm carbon on a bias around the fuse extending back a full 6" aft of the pod, and I'm also putting 12k tow 18" down each side like I would with a conventional boom. This should make the boom more survivable in launch, and much more stiff as well, at the cost of about 5-8g just behind the CG. In my opinion, this is a great tradeoff.

I start by cutting some carbon on a bias and spraying it with 3m77 to stick it in place. Next I do the same with 3m77 and the tow. Be very careful when doing this... bias light cloth with sticky spray on it can be quite unruly, as can tow. Next I wet it out (mixing 2.8g of MGS) by rubbing the epoxy in with a thumb and forefinger, always moving from the center toward the ends of the tow. Last, I wet out the bias 80g/sm cloth and blot it well with paper towels.

Once everything is sufficiently wet, then dried, I wrap with a piece of VCR tape as tightly as I can without damaging the boom underneath. This makes a good evening of work for our first night out.

I have trouble finding colors that show up for me. This one does for whatever it's worth. Yellow and Red are horrible for me, especially against a grey sky, which seems to be all we get at DLG contests.

Images

Now it's on to the wing. The servo pockets are relieved and the slots are cut for the control horns. Normally I don't use the horns included with kits or airplanes, but in this case they're works of art so I will be using them. The blaster has ribs in the wing on either side of the servo bay to help with stiffness. Horns are aligned using the included servo covers to determine the centerline for the pushrods.

Always ensure the horns are perpendicular to the flapperon surface, ensure that the horn is bonded securely to BOTH skins, and try to keep the amount of material removed to accomodate the horn as small as possible. Use a sharp blade and don't cut quickly. You don't want to create delaminations around the cutting area, especially if using epoxy since it won't "wick" in and re-bond those areas.

For gluing the horns in place on molded ships, I use laminating epoxy (in this case MGS) with a fast hardener and a bit of milled glass or cotton.

Time for radio gear. For this one, I'm switching from JR to Airtronics, not just in servos, but all around. I have some comparisons below of the 5ch full range Airtronics receiver and the Spektrum AR6250 that I used to fly. I also compared the JR241/285 servo case to the Hyperion / Airtronics 802s that I'll be using.

This year I'm also using LiPos and regulators for the first time. Last season I used CR2s all year (successfully) but the Cali guys are giving me some crap about being more environmentally friendly so I switched. I promise I'll dispose of the LiPos properly